The Sitemap XML protocol is also extended to provide a way of listing multiple Sitemaps in a 'Sitemap index' file. The maximum Sitemap size of 50 MiB or 50,000 URLs means this is necessary for large sites. An example of Sitemap index referencing one separate sitemap follows.
Cultural or artificial eutrophication occurs when human activity introduces increased amounts of these nutrients, which speed up plant growth and eventually choke the lake of all of its animal life.n nature, eutrophication is a common phenomenon in freshwater ecosystems and is really a part of the normal aging process of many lakes and ponds. Some never experience it because of a lack of warmth and light, but many do.
There are two types of eutrophication: natural eutrophication and anthropogenic eutrophication. Eutrophication is widespread in freshwater ecosystems, and it plays a major role in the normal aging process of many ponds and lakes. The main cause of anthropogenic eutrophication is human activity. Nutrients from fertilized fields, lawns, and farms are deposited in rivers, streams, lakes and oceans when it rains.